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Arsenic project

Arsenic and the Environment

Arsenic is a natural metal-like chemical that is found in groundwater all over the world.  It has no odor or taste. It is a toxic element that occurs naturally in air, water, soil, rocks and minerals, and shows up in food and living organisms in low concentrations.
Arsenic occurs naturally in rocks and soil, water, air, plants and animals.  It can be further released into the environment through natural activities such as volcanic action, erosion of rocks and forest fires, or through human actions.  Arsenic contamination of groundwater can also sometimes be traced to deep-water brines produced from gas and oil well drilling or from industrial activities like semiconductor manufacturing.
Arsenic cannot be destroyed; it can only change its form. When absorbed or ingested by animals and plants, arsenic combines with carbon and hydrogen to form organic arsenic compounds.  High arsenic levels can also come from certain fertilizers and animal feeding operations.  Arsenic is absorbed by all plants, but is more concentrated in leafy vegetables, rice, apple and grape juice.  Seafood may also contain arsenic in high concentrations.
Approximately 90 percent of industrial arsenic in the U.S. is currently used as a wood preservative, but it is also an ingredient in paints, dyes and metals.  Arsenic and its compounds are important in the production of pesticides, herbicides and insecticides. 
Higher levels of arsenic tend to be found more in ground water than in surface water like lakes and rivers.  Increasing demand on ground water from municipal systems and private drinking water wells may cause water levels to drop and release arsenic from rock formations.  In some areas of the world, natural levels of arsenic in the water are extremely dangerous and hard to detect.  Arsenic can enter drinking water from natural deposits in the earth, from agricultural and industrial practices, and from wind-blown dust. 
Arsenic is one of nature's most toxic elements.  Humans may be exposed to arsenic through food, water and air.  Exposure may also occur through skin contact with soil or water that contains arsenic.  Human exposure to arsenic can cause both short-term and long-term health effects. Long-term exposure has been associated with cancer in nasal passages, as well as skin, lung, urinary bladder, liver, kidney and prostate.  Low levels can cause skin lesions, diarrhea and other symptoms.  It can also cause other skin changes such as thickening and changes in coloration.
The likelihood of effects is related to the level of exposure to arsenic; in areas where drinking water is heavily contaminated, these effects can be seen in much of the local population.  Increased incidence of lung and bladder cancer and skin changes have been reported in people ingesting arsenic.  Exposure to arsenic in the workplace by inhalation can also cause lung cancer.  Smoking and arsenic exposure combined dramatically increases the risk of lung cancer.  Other health effects of arsenic include stomach pain, nausea, vomiting, numbness in hands and feet, partial paralysis, developmental and reproductive effects, diabetes and blindness.
A urine test is a simple way to tell if you are currently being exposed to arsenic at levels of concern in your drinking water.  However, this test will not tell you what type of arsenic is in your body.  To get the most accurate urine test results, do not eat any fish or seafood for at least three days before your test.  If needed, your doctor has additional tests that can be performed to check arsenic levels in your body.
Arsenic is regulated in public drinking water systems by the Environmental Protection Agency and an allowable limit, known as a maximum contaminant level has been established. The EPA has also set limits on the amount of arsenic that industry can release into the environment.
If your water comes from a municipal or privately-owned water company that meets the definition of a
community water system, they are most likely testing for arsenic in your water.  If the arsenic
maximum contaminant level is exceeded, the public water system must issue a notice to customers,
in writing, within 30 days of the violation.  Customers would be notified immediately through broadcast media in the unlikely event contamination levels were high enough to cause acute health effects.
If you have your own household water supply, you are responsible for maintaining and testing it.  Because the amount of arsenic in well water can vary throughout the year, you should test for it in late summer and in the early spring to see if there are seasonal differences.  Laboratories usually charge a modest fee for the test.  Even though private wells are not regulated, if the level in your private well exceeds the public drinking water standard, you are urged to consider taking steps to reduce your long-term exposure to those levels of arsenic.
During well construction and normal water sampling, the water is usually not tested for arsenic.  Your local health department can provide a list of certified state and commercial laboratories that, for a fee, will test for arsenic in your water.  Your local environmental health office can help you make arrangements for water testing and respond to your questions.
There are several ways to reduce your exposure to arsenic in your well water. If you have high levels of arsenic in your water you should talk to your local health department or the Pennsylvania Department of Health before making your choice.  Drinking and cooking with bottled water can reduce your exposure instantly while you consider your options. There are options to treat your well water.  Some home water treatment systems that use reverse osmosis, distillation or special filtration material can reduce the amount of arsenic in the water. You may consider a new well installed at a different location or depth.  Also, it may be possible to connect to a public water supply or community well if one is nearby.  Contact your local water utility to ask about the possibility of connecting to a public supply.  Long-term measures usually involve installation of a home-treatment device that can remove arsenic and should be used for any water that will be consumed by you and your family members. Bathing and hand washing, washing laundry and flushing toilets are examples of water uses that do not require treatment.  You cannot remove arsenic by boiling the water. In fact, you may only increase the concentration of arsenic in the water that remains after boiling.
If you have unanswered concerns or questions, consult your local health department for information on a testing laboratory. The lab must be certified to do drinking water testing.  You may also wish to talk with your state geological survey office or a United States Department of Agriculture agent.